The Relationship between Bacterial Load and Initial Run Time of a Surgical Helmet.

Background: Periprosthetic joint infection (PJI) is a complication of arthroplasty surgery with significant morbidity and mortality. Surgical helmets are a possible source of infection. Pre-existing dust and microorganisms on its surface may be blown into the surgical field by the helmet ventilation system. Methods: Twenty surgical helmets at our institution were assessed through microscopy and polymerase chain reaction testing. Helmets were arranged with agar plates under the front and rear outflow vents. Helmets ran while plates were exchanged at different time points. Bacterial growth was assessed via colony counts and correlated with fan operating time. Gram staining and 16S sequencing were performed to identify bacterial species. Results: The primary microbiological contaminate identified was Burkholderia. There was an inverse relationship between colony formation and fan operating time. The highest number of colonies was found within the first minute of fan operating time. There was a significant decrease in the number of colonies formed from the zero-minute to the three (27 vs 5; P = <.01), four (27 vs 3; P = <.01), and five-minute (27 vs 4; P = <.01) time points for the front outflow plates. A significant difference was also observed between the one-minute and four-minute time points (P = .046). Conclusion: We observed an inverse relationship between bacterial spread helmet fan operation time, which may correlate with dispersion of pre-existing contaminates. To decrease contamination risk, we recommend that helmets are run for at least 3 min prior to entering the operating room.

Range of motion following percutaneous fixation of pediatric supracondylar humerus fracture is independent of anterior osseous fragment resorption.

The objective of this study was to understand postoperative resorption of the anterior osseous fragment following closed reduction and percutaneous pinning (CRPP) of pediatric supracondylar humerus fractures and its effect on final range of motion (ROM). Eighty-six patients that underwent CRPP had sagittal and or axial plane deformities resulting in an anterior fragment. Humerocapitellar angle (HCA), anterior humeral line (AHL) and angle of rotation (AoR) were measured. A total of 11 (12.8%) patients failed to resorb the anterior fragment, 10 (90.9%) had satisfactory ROM. HCA initially was acceptable in 40 (46.5%) patients, and 37 (92.5%) demonstrated acceptable ROM. Final HCA was acceptable in 44 (51.2%) patients and 42 (95.4%) had acceptable final ROM. AHL was in the anterior third of the capitellum in 35 (40.6%) patients and 33 (94.3%) had acceptable ROM. Final AHL was in the anterior third of the capitellum in 43 (50.0%) patients and 41 (95.3%) had acceptable final ROM. No difference was found between acceptable ROM and HCA or AHL at either follow-up. Sixty-five and 21 patients had an AoR of 0° and between 23 and 36°, respectively. A total of 59 (90.7%) patients with an AoR of 0°, and 18 (85.7%) patients with an AoR of 23-36° displayed acceptable ROM. A total of 57 (87.7%) patients with an AoR of 0° and 18 (85.7%) with an AoR of 23-36° resorbed the anterior fragment. No association was found between rotational deformity and postoperative ROM or fragment resorption. Postoperative sagittal and axial plane alignment, HCA, AHL, AoR and resorption of the anterior osseous fragment does not correlate with final ROM.